Display panel and method of manufacturing thereof

ABSTRACT

The present application discloses a display panel and method of manufacturing thereof. The display panel of the present application includes a substrate, an active switch, a color photoresist layer, a first electrode layer, a light emitting diode, a second electrode layer, an encapsulation layer and a driver circuit. The light emitting diode includes a red light emitting layer, a green light emitting layer and a blue light emitting layer which includes a silicon-germanium quantum dot material.

This application is a Divisional of U.S. patent application Ser. No.16/349,593 filed on May 13, 2019. The present application claimspriority to Chinese patent application No. CN201811306319.1, filed withthe Chinese Patent Office on Nov. 5, 2018, and entitled “DISPLAY PANELAND METHOD OF MANUFACTURING THEREOF”, which is incorporated herein byreference in its entirety.

TECHNICAL FIELD

The present application relates to the field of display technique,particularly to a display panel and method of manufacturing thereof.

BACKGROUND

The statement here merely provides background information relative tothe present application, but not necessarily constitutes the prior art.

Displays known by the inventor are generally controlled by activeswitches. The displays are widely used for having a variety ofadvantages such as thin, power saving and radiation-free and are mainlyincluded of liquid crystal displays, Organic Light-Emitting Diode (OLED)displays, Quantum Dot Light Emitting Diode (QLED) displays, plasmadisplays, etc. In terms of apparent structures, both flat type andcurved type of displays are included.

With the liquid crystal displays, a liquid crystal panel and a backlightmodule are included. The principle of operation for the liquid crystaldisplays is to dispose liquid crystal molecules between two parallelglass substrates and apply a driving voltage to the two glass substratesso as to control a rotation direction of the liquid crystal molecules,thereby refracting lights from a backlight module for producing ascreen.

With the OLED displays, an organic light emitting diode is configured toemit lights for displaying. The OLED displays have advantages such asself-luminescence, wide angle of view, almost infinitely high contrast,lower power consumption and high-speed response. In comparison withorganic fluorescence luminophors, light emission based on quantum dothas advantages such as high color purity, long lifetime and easydispersion and may be manufactured by a printing process. Thus, QLED iscommonly considered as a strong contender for the next generation ofdisplay technique. Current OLEDs are low in composite efficiency andshort in lifetime.

SUMMARY

The present application is to provide a display panel so as to improvethe performance of a transistor.

The object of the present application is achieved by the followingtechnical solutions.

According to one aspect of the present application, the presentapplication discloses a display panel, including:

-   -   a substrate;    -   an active switch formed on the substrate;    -   a color photoresist layer formed on the active switch;    -   a first electrode layer formed on the color photoresist layer;    -   a light emitting diode formed on the first electrode layer;    -   a second electrode layer formed on the light emitting diode;    -   an encapsulation layer formed on the second electrode layer;    -   a driver circuit electrically connected with the first and        second electrode layers;    -   the light emitting diode includes a red light emitting layer, a        green light emitting layer and a blue light emitting layer, each        of which includes a silicon-germanium quantum dot material;    -   a proportion of silicon in the red light emitting layer ranges        from 10%-35% and that of germanium ranges from 65%-90%; the        proportion of silicon in the green light emitting layer ranges        from 45%-65% and that of germanium ranges from 35%-50%; the        proportion of silicon in the blue light emitting layer ranges        from 65%-95% and that of germanium ranges from 5%-35%.

According to another aspect of the present application, the presentapplication also discloses a method of manufacturing a display panel,including:

-   -   forming an active switch on a substrate;    -   forming a color photoresist layer on the active switch;    -   forming a first electrode layer on the color photoresist layer;    -   forming a light emitting diode on the first electrode layer;    -   forming a second electrode layer on the light emitting diode;    -   forming an encapsulation layer on the second electrode layer;    -   disposing a driver circuit in electrical connection with the        first and second electrode layers;    -   the light emitting diode includes a red light emitting layer, a        green light emitting layer and a blue light emitting layer, each        of which includes a silicon-germanium quantum dot material.

According to another aspect of the present application, the presentapplication also discloses a display device including a display panel,the display panel including:

-   -   a substrate;    -   an active switch formed on the substrate;    -   a color photoresist layer formed on the active switch;    -   a first electrode layer formed on the color photoresist layer;    -   a light emitting diode formed on the first electrode layer;    -   a second electrode layer formed on the light emitting diode;    -   an encapsulation layer formed on the second electrode layer;    -   a driver circuit electrically connected with the first and        second electrode layers;    -   the light emitting diode includes a red light emitting layer, a        green light emitting layer and a blue light emitting layer, each        of which includes a silicon-germanium quantum dot material;    -   a proportion of silicon in the red light emitting layer ranges        from 10%-35% and that of germanium ranges from 65%-90%; the        proportion of silicon in the green light emitting layer ranges        from 45%-65% and that of germanium ranges from 35%-50%; the        proportion of silicon in the blue light emitting layer ranges        from 65%-95% and that of germanium ranges from        5%-35%.Optionally, the step of forming the light emitting diode        on the first electrode layer includes a method of manufacturing        the blue light emitting layer:    -   forming a plastic cluster;    -   forming rods with the plastic clusters;    -   arranging the rods in a hexagon form so as to form a hexagonal        matrix;    -   forming an intermediate template set with the hexagonal matrices        according to a self-assembling mechanism of organic molecular        template;    -   roasting the intermediate template set to remove the template so        as to form a silica frame;    -   filling the silica frame with the silicon-germanium quantum dot        material.

In a technique for self-assembling molecular template via silica framesof the present application, mesoporous silica has a specific porestructure, which is hollow, low in density and large in specific surfacearea. Thus, the mesoporous silica has unique penetrability, moleculesieving ability, optical performance and adsorption and can improve theproperty of the blue light emitting layer. Furthermore, due to highelectron mobility, the germanium material can improve the light emissionefficiency of three-series QLED. Therefore, the electrical conductivityof the backlight source of the three-series QLED is effectivelyimproved, thereby improving the composite performance of thethree-series QLED and extending the lifetime thereof.

BRIEF DESCRIPTION OF DRAWINGS

The drawings are included to provide understanding of embodiments of thepresent application, which constitute a part of the specification andillustrate the embodiments of the present application, and describe theprinciples of the present application together with the textdescription. Apparently, the accompanying drawings in the followingdescription show merely some embodiments of the present application, anda person of ordinary skill in the art may still derive otheraccompanying drawings from these accompanying drawings without creativeefforts. In the accompanying drawings:

FIG. 1 is a structural schematic diagram of a display panel according toan embodiment of the present application;

FIG. 2 is a structural schematic diagram of a light emitting diodeaccording to an embodiment of the present application;

FIG. 3 is a structural schematic diagram of a display device accordingto an embodiment of the present application;

FIG. 4 is a structural schematic diagram of an active switch accordingto an embodiment of the present application;

FIG. 5 is a schematic diagram of a method of manufacturing a displaypanel according to an embodiment of the present application;

FIG. 6 is a schematic diagram of a method of manufacturing a lightemitting diode according to an embodiment of the present application;

FIG. 7 is a schematic flow diagram of a method of forming a silica framethrough self-assembling a molecular template according to an embodimentof the present application;

FIG. 8 is a schematic diagram of a technique for self-assembling amesoporous silica frame according to an embodiment of the presentapplication;

FIG. 9 is a schematic diagram of a method of preparing a nano-poroussilica medium according to an embodiment of the present application;

FIG. 10 is a schematic flow diagram of a method of forming a silicaframe through self-assembling a molecular template according to anembodiment of the present application;

DETAILED DESCRIPTION

The specific structural and functional details disclosed in theembodiments of the present application are merely representative, andare for the purpose of describing exemplary embodiments of the presentapplication. However, the present application can be specificallyembodied in many alternative forms, and should not be interpreted to belimited to the embodiments described herein.

In the description of the present application, it should be understoodthat, orientation or position relationships indicated by the terms“center”, “transversal”, “upper”, “lower”, “left”, “right”, “vertical”,“horizontal”, “top”, “bottom”, “inner”, “outer”, etc. are based on theorientation or position relationships as shown in the drawings, for easeof the description of the present application and simplifying thedescription only, rather than indicating or implying that the indicateddevice or element must have a particular orientation or be constructedand operated in a particular orientation. Therefore, these terms shouldnot be understood as a limitation to the present application. Inaddition, the terms such as “first” and “second” are merely for adescriptive purpose, and cannot be understood as indicating or implyinga relative importance, or implicitly indicating the number of theindicated technical features. Hence, the features defined by “first” and“second” can explicitly or implicitly include one or more features. Inthe description of the present application, “a plurality of” means twoor more, unless otherwise stated. In addition, the term “include” andany variations thereof are intended to cover a non-exclusive inclusion.

In the description of the present application, it should be understoodthat, unless otherwise specified and defined, the terms “install”,“connected with”, “connected to” should be comprehended in a broadsense. For example, these terms may be comprehended as being fixedlyconnected, detachably connected or integrally connected; mechanicallyconnected or electrically connected; or directly connected or indirectlyconnected through an intermediate medium, or in an internalcommunication between two elements. The specific meanings about theforegoing terms in the present application may be understood by thoseskilled in the art according to specific circumstances.

The terms used herein are merely for the purpose of describing thespecific embodiments, and are not intended to limit the exemplaryembodiments. As used herein, the singular forms “a”, “an” are intendedto include the plural forms as well, unless otherwise indicated in thecontext clearly. It will be further understood that the terms “comprise”and/or “include” used herein specify the presence of the statedfeatures, integers, steps, operations, elements and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components and/or combinationsthereof.

Detailed description is optionally made for the present implementationin connected with FIGS. 1-10 and optional embodiments.

With reference to FIGS. 1 and 8-10, the present implementation disclosesa display panel, including:

-   -   an encapsulation layer 31;    -   a first electrode layer 32 disposed on the encapsulation layer        31;    -   a light emitting diode 33 disposed on the first electrode layer        32;    -   a second electrode layer 34 disposed on the light emitting diode        33; and    -   a driver circuit 35 electrically connected with the first        electrode layer 32 and the second electrode layer 34.

The light emitting diode 33 includes a red light emitting layer 40, agreen light emitting layer 44 and a blue light emitting layer 36, eachof which includes a silicon-germanium quantum dot material 14.

A proportion of silicon in the red light emitting layer ranges from10%-35% and that of germanium ranges from 65%-90%. The proportion ofsilicon in the green light emitting layer ranges from 45%-65% and thatof germanium ranges from 35%-50%. The proportion of silicon in the bluelight emitting layer ranges from 65%-95% and that of germanium rangesfrom 5%-35%.

In an embodiment, the blue light emitting layer 36 includes a silicaframe 10 which is made from a mesoporous material 16 (i.e., a mesoporoussilica material). A silicon-germanium quantum dot material 14 is formedwithin the silica frame 10 which includes several cylindrical holes 12.The holes 12 run through the silica frame 10 and are filled with thesilicon-germanium quantum dot material 14. Silicon and germanium arealso embedded into silica hole walls 11. The silica frame 10 includesseveral cylindrical holes 12. The holes 12 run through the silica frame10 and are filled with the silicon-germanium quantum dot material 14. Itis convenient to use a self-assembling molecular template solution oxideto implement the structure with holes 12. The holes 12 may be eithercylindrical or polygonal. The structures with holes 12 in differentshapes can be accomplished according to different processes and productdemands. Therefore, the structures with holes 12 in various shapes fallin the conceptual scope of the present implementation.

In an embodiment, the holes 12 are disposed in a hexagonal pattern. Thearrangement in the hexagonal pattern may form a honeycomb like structurewhich is good in stability.

In an embodiment, the holes 12 have a diameter D1 in the range of 2-7nanometers, and the walls thereof have a thickness D2 in the range of1-2 nanometers. The thickness of the walls of the holes 12 range from1-2 nanometers. Oversize and undersize are both not appropriate for theholes and the walls thereof. The performance of the blue light emittinglayer 36 may be ensured when the diameter of the holes 12 ranges from2-7 nanometers and the thickness of the walls thereof ranges from 1-2nanometers.

In an embodiment, the molecular template 13 includes hole walls madefrom silica material. Nano crystals 15 of indium gallium zinc oxide(IGZO) material containing chemical elements silicon and germanium areformed on the hole walls.The molecular template 13 also has a hollowstructure, so that the nano crystals 15 of IGZO material may beuniformly mixed with the mesoporous silica, thereby improving electricalconductivity.

A quantum dot is a zero dimensional system of low-dimensional systems.The typical structure is the dimension thereof is limited within aregion of 100 nm, which is shorter than a mean free path of an electron(an average distance travelled by a moving electron between twosuccessive collisions).The quantum dot consists of one or moresemiconductors. Different light emitting color may be obtained bycontrolling the size of the quantum dot.

When a light beam reaches the semiconductor material, electrons in thevalence band jump out and into the conduction band after thesemiconductor material absorbs photons. The electrons in the conductionband can also jump back into the valence band to emit photons or fallinto electron traps of the semiconductor material.

The principle for charge injection of the quantum dot can be introducedusing following three steps.

Firstly, when a positive outward bias is applied, a hole and an electronovercome an energy barrier at an interface and enter a valence bandlevel of the hole transport layer and a conduction band level of theelectron transport layer respectively via anode and cathode injections.

Secondly, due to the level difference of external electric fields, thehole and electron cause charge accumulation at the interface.

Thirdly, an exciton is formed after the electron and the hole arerecombined in the quantum dot. Since a sub-excitation state is not verystable in a general environment and energy is released in the forms oflight and heat so as to return to a stable ground state,electroluminescence is a phenomenon of current driving.

In the self-assembling molecular template technique of silica frames,mesoporous silica has a specific pore structure, which is hollow, low indensity and large in specific surface area. Thus, the mesoporous silicahas unique penetrability, molecule sieving ability, optical performanceand adsorption and can improve the property of the blue light emittinglayer. Furthermore, due to high electron mobility, the germaniummaterial can improve the light emission efficiency of three-series QLED.Therefore, the electrical conductivity of the backlight source of thethree-series QLED is effectively improved, thereby improving thecomposite performance of the three-series QLED and extending thelifetime thereof. The molecular template self-assembling technique ofthe silicon-germanium nano IGZO (GE, SiGe) is utilized in the presentimplementation as a precursor IGZO source of an object such that thesilicon-hydroxyl functional group at the surface of the moleculartemplate of the subject can be converted into nano dots necessary fornano IGZO, germanium and silicon. The electrical conductivity of theblue light emitting layer is thus substantially increased, therebyimproving the performance of the QLED.

The embodiment shown in FIG. 2 discloses a specific light emitting diode33, including:

-   -   the electron injection layer 37 electrically connected with the        first electrode layer 32;    -   the first electron transport layer 39 formed on the electron        injection layer 37, the red light emitting layer 40 being formed        on the first electron transport layer 39;    -   the first hole transport layer 41 formed on the red light        emitting layer 40;    -   the first intermediate connector 42 formed on the first hole        transport layer 41;    -   the second electron transport layer 43 formed on the first        intermediate connector 42, the green light emitting layer 44        being formed on the second electron transport layer 43;    -   the second hole transport layer 45 formed on the green light        emitting layer 44;    -   the second intermediate connector 46 formed on the second hole        transport layer 45;    -   the third electron transport layer 47 formed on the second        intermediate connector 46;    -   the blue light emitting layer 36 formed on the third electron        transport layer 47;    -   the third hole transport layer 48 formed on the blue light        emitting layer 36; and    -   the hole injection layer 49 formed on the third hole transport        layer 48 and electrically connected with the second electrode        layer 34.

The specific construction of the blue light emitting layer may be foundwith reference to the abovementioned implementation and is not repeatedhere.

With reference to FIG. 3, the present implementation discloses a displaydevice including a display panel and the display panel described in thepresent application. The display panel includes:

-   -   a substrate 23;    -   a plurality of active switches 52 formed on the substrate 23;        and    -   a plurality of color photoresist layers 51 formed on the active        switches 52.

The second electrode layer 34 is overlaid on the plurality of colorphotoresist layers 51 and is made from a transparent conductivematerial, e.g., indium tin oxides (ITOs).The specific constructions ofthe display panel and the blue light emitting layer 36 may be found withreference to the abovementioned implementation and are not repeatedhere.

The implementation shown in FIG. 4 discloses a specific structure of anactive switch 52, which includes:

-   -   a source electrode 24 and a drain electrode 25 formed on the        substrate 23 of the display panel;    -   two slope structures 30 formed on the substrate 23 and        respectively covering the source electrode 24 and the drain        electrode 25, a groove structure being formed between the two        slope structures 30;    -   a semiconductor layer 27 disposed between the two slope        structures 30 and connecting the source electrode 24 with the        drain electrode 25;    -   a dielectric layer 28 disposed between the two slope structures        30 and formed on the semiconductor layer 27;    -   a gate electrode 26 formed on the dielectric layer 28; and    -   a passivation layer 29 formed on the gate electrode 26.

The semiconductor layer 27 includes the silica frame 10 in which thesynthetic nano-material containing indium gallium zinc oxide isdisposed. The silica frame 10 has a specific pore structure, which ishollow, low in density and large in specific surface area. Thus, themesoporous silica 10 has unique penetrability, molecule sieving ability,optical performance and adsorption and can improve the property of thesemiconductor layer 27. The molecular template self-assembling techniqueof the silicon-germanium nano IGZO (GE, SiGe) is utilized in the presentimplementation as a precursor IGZO source of an object such that thesilicon-hydroxyl functional group at the surface of the moleculartemplate of the subject can be converted into nano dots necessary fornano IGZO, germanium and silicon. The electrical conductivity of thesemiconductor layer 27 is thus substantially increased, therebyimproving the performance of the TFT.

With reference to FIG. 5, the present implementation discloses a methodof manufacturing the display panel, including:

S51: Form an active switch on a substrate.

S52: Form a color photoresist layer on the active switch.

S53: Form a first electrode layer on the color photoresist layer.

S54: Form a light emitting diode on the first electrode layer.

S55: Form a second electrode layer on the light emitting diode.

S56: Form an encapsulation layer on the second electrode layer.

S57: Dispose a driver circuit in electrical connection with the firstand second electrode layers.

The light emitting diode includes a red light emitting layer, a greenlight emitting layer and a blue light emitting layer, each of whichincludes a silicon-germanium quantum dot material.

In the self-assembling molecular template technique of silica frames ofthe present application, mesoporous silica has a specific porestructure, which is hollow, low in density and large in specific surfacearea. Thus, the mesoporous silica has unique penetrability, moleculesieving ability, optical performance and adsorption and can improve theproperty of the blue light emitting layer. Furthermore, due to highelectron mobility, the germanium material can improve the light emissionefficiency of the QLED. Therefore, the electrical conductivity of thebacklight source of the QLED is effectively improved, thereby improvingthe composite performance of the QLED and extending the lifetimethereof. The specific construction of the blue light emitting layer maybe found with reference to the abovementioned implementation and is notrepeated here.

With reference to FIGS. 6-10, the present implementation discloses amethod of manufacturing the blue light emitting layer of the lightemitting diode, including:

S61: Form a plastic cluster 18.

S62: Form rods 19 with the plastic clusters 18.

S63: Arrange the rods 19 in a hexagon form so as to form a hexagonalmatrix 20.

S64: Form an intermediate template set with the hexagonal matrices 20according to a self-assembling mechanism of organic molecular template.

S65: Roast the intermediate template set to remove the template so as toform a silica frame 10.

S66: Fill the silica frame 10 with the silicon-germanium quantum dotmaterial 14.

The hexagonal matrices consisting of rods 19 made of plastic clustersare used as templates which are both shaping agent and stabilizing agentper se. The desired adjustment and control of the material structure canbe achieved through changing the shape and size of the templates. Also,the experimental devices are simple and easy in operation. Further, therods 19 can be reused, which reduces wastes and has benefits of reducingcost and environmental pollution. The specific constructions of thedisplay panel and the blue light emitting layer may be found withreference to the abovementioned implementation and are not repeatedhere.

The abovementioned embodiments, the active switches may be thin-filmtransistors, and the display panel may include a liquid crystal panel, aplasma panel, an OLED panel, a QLED panel and the like. Moreover, thedisplay panel may be either a flat type panel or a curved type panel.

The foregoing are optional detailed description of the presentapplication in connection with specific optional embodiments and are notconsidered as limiting of the embodiments of the present application.Various simple deductions and substitutions may be made by persons ofordinary skills in the art of the present application without departingfrom the spirit of the present application and should be considered aswithin the scope of protection of the present application.

What is claimed is:
 1. A method of manufacturing a display panel,comprising: forming an active switch on a substrate; forming a colorphotoresist layer on the active switch; forming a first electrode layeron the color photoresist layer; forming a light emitting diode on thefirst electrode layer; forming a second electrode layer on the lightemitting diode; forming an encapsulation layer on the second electrodelayer; and disposing a driver circuit in electrical connection with thefirst and second electrode layers; wherein the light emitting diodecomprises a red light emitting layer, a green light emitting layer and ablue light emitting layer, each of which comprises a silicon-germaniumquantum dot material, a proportion of silicon in the red light emittinglayer ranges from 10%-35% and that of germanium ranges from 65%-90%; theproportion of silicon in the green light emitting layer ranges from45%-65% and that of germanium ranges from 35%-50%; the proportion ofsilicon in the blue light emitting layer ranges from 65%-95% and that ofgermanium ranges from 5%-35%.
 2. The method of manufacturing a displaypanel according to claim 1, wherein the step of forming the lightemitting diode on the first electrode layer comprises a method ofmanufacturing the blue light emitting layer: forming plastic clusters;forming rods with the plastic clusters; arranging the rods in a hexagonform so as to form hexagonal matrices; forming an intermediate templateset with the hexagonal matrices according to a self-assembling mechanismof organic molecular template; roasting the intermediate template set toremove the template so as to form a silica frame; and filling the silicaframe with the silicon-germanium quantum dot material.
 3. The method ofmanufacturing a display panel according to claim 1, wherein the step offorming a second electrode layer on the light emitting diode comprises:forming an electron injection layer, the electron injection layerelectrically connected with the first electrode layer; forming a firstelectron transport layer on the electron injection layer, the red lightemitting layer being formed on the first electron transport layer;forming a first hole transport layer on the red light emitting layer;forming a first intermediate connector on the first hole transportlayer; forming a second electron transport layer on the firstintermediate connector, the green light emitting layer being formed onthe second electron transport layer; forming a second hole transportlayer on the green light emitting layer; forming a second intermediateconnector on the second hole transport layer; forming a third electrontransport layer on the second intermediate connector; forming the bluelight emitting layer on the third electron transport layer; forming athird hole transport layer on the blue light emitting layer; and forminga hole injection layer on the third hole transport layer andelectrically connected with the second electrode layer.
 4. The method ofmanufacturing a display panel according to claim 2, wherein the silicaframe comprises several cylindrical holes; the holes run through thesilica frame and are filled with the silicon-germanium quantum dotmaterial.
 5. The method of manufacturing a display panel according toclaim 4, wherein the holes are disposed in a hexagonal pattern.
 6. Themethod of manufacturing a display panel according to claim 4, whereinthe holes have a diameter in a range of 2-7 nanometers, and the wallsthereof have a thickness in a range of 1-2 nanometers.
 7. The method ofmanufacturing a display panel according to claim 3, wherein the redlight emitting layer and the green light emitting layer each comprises asilica frame which has the silicon-germanium quantum dot material formedtherein and comprises several cylindrical holes; the holes run throughthe silica frames and are filled with the silicon-germanium quantum dotmaterial.
 8. The method of manufacturing a display panel according toclaim 1, wherein the step of forming a color photoresist layer on theactive switch comprises: forming a source electrode and a drainelectrode formed on the substrate of the display panel; forming twoslope structures on the substrate and respectively covering the sourceelectrode and the drain electrode, a groove structure being formedbetween the two slope structures; forming a semiconductor layer disposedbetween the two slope structures and connecting the source electrodewith the drain electrode; forming a dielectric layer on thesemiconductor layer, and disposed between the two slope structures;forming a gate electrode on the dielectric layer; and forming apassivation layer on the gate electrode; wherein the semiconductor layercomprises a silica frame in which a synthetic nano-material containingindium gallium zinc oxide is disposed.
 9. The method of manufacturing adisplay panel according to claim 2, wherein the silica frame is madefrom a mesoporous silica material.
 10. The method of manufacturing adisplay panel according to claim 2, wherein the molecular templatecomprises a hole walls made from a silica material Nano crystals ofindium gallium zinc oxide (IGZO) material containing chemical elementssilicon and germanium are formed on the hole walls.